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Efficiency Disappointment?

Well, it has been one month since my new Lennox XP 19 Heat pump and variable speed furnace has been in use. I am surprised to find that it is using more energy than my 22 year old Lennox 6 SEER. The system is working great in terms of cooling, but the energy use is 18&#37; greater and when adjusted for my hot tub power being turned off at the same install time, the difference is even greater. The t-stat settings have been the same as before and when I look at the high outdoor temp and take that into account for that increase in June’s energy use it is still baffling why the new Lennox is more of a energy hog. Nothing else in the house has changed. The figures below came from my power company. I installed the new dual fuel system on May 30, 2008.

If you're home isn't insulated properly and you have leaky windows and doors. Basically an older home. It doesn't matter what SEER rating you put in if it can't keep cold in and hot out or vice versa. You really need to look at the entire picture and not think that a fancy A/C system is gonna solve the problem. Maybe the ducts are too small as well, is the return undersized? It could be setup wrong. I've setup a few, they aren't that hard, but you do have to wire everything and cut jumpers and set dipswitches.

For 20 days before new system average temp was 80.5, and average KW 108.95
For 20 days after install average temp was 88.55, and average KW 110.9

Those numbers look better to me

What about relative humidity? You may be jumping the gun a little here. try comparing this summer to last summer. I am not saying that the new system is set up properly, there is not enough information to tell that from your post. And this is a kind of small sample. The numbers change a lot from day to day there so there must be a lot of other variables in this picture....

I r the king of the world!...or at least I get to stand on the roof and look down on the rest of yall

That's what I'm wondering. If it is the same old duct system as the old system had, and has the air leaks and inadequate insulation that are typical of old duct systems, heat gain and duct leakage will cripple 1st stage of a new 2 stage system.
When it is installed on an old leaky and poorly insulated duct system, it is not uncommon for a new ultra efficient 2 stage system to actually use more energy than the old inefficient 1 stage system did.

The reason this can happen is that the old system had enough capacity to still cool the house, despite the duct leakage and heat gain.
The new 2 stage system doesn't have enough capacity in 1st stage to overcome the duct leakage and heat gain, which is increased due to the lower velocity airflow in 1st stage, and still cool effectively, so you end up with much longer run times, and the system going into 2nd stage much more often.
We will see this more and more often due to the proliferation of 2 stage equipment.

I'm not saying that this is what is happening in this case, just pointing it out as a possibility.

A current clamp would tell a lot, but since you didn't already, you don't have one. Your backwards rolling date gives me a migrane...

Comparing the ratio of daily KWH consumption to daily high deviation from (lets say 70F), Appears that you have an electric dryer, and you do laundry 50% consistantly on Sunday nights, registering for Mondays? Is your spa electric? Appears that during the two months of log, you used it only on: Wed 5/7/2008 and Thursday 5/22/2008.

Since the plot started, you have gone from little heating season to cooling season, so analyzing the data is a bit complex.

Turn the HVAC off for 24 hours and carry on with your other consumption. Do you know at what time the KWH log starts? If so, turn the HVAC off that moment for 24 hours. If you don't know the start and stop time, turn the HVAC off for 48 hours. You will have at least on full 24 hour period with the HVAC off, which should be obvious in the KWH report.